I. Salinas-Ortega et al. / Journal of Molecular Structure 1128 (2017) 361e367
363
1
24.7 (C4), 129.7 (C2 and C6), 131.3 (C6), 132.6(C3 and C5), 135.3
was dissolved in methanol. Then, sodium carbonate (18 mg,
0.17 mmol) was added and allowed to react for 2 h at room tem-
perature. Then, the reaction mixture was filtered and concentrated
under vacuum. The resulting solid mixture, was purified by column
chromatography (silica gel 60, ethyl acetate: hexane ¼ 1:10 v/v).
0
0
(
C1), 136.8 (C4 ), 143.8 (Cb), 162.2 (C2 ), 193.8 (-C]O). Analysis
calculated for C17
H
12
O
2
: C, 82.24; H, 4.87; O, 12.89. Found: C, 81.13;
þ
H, 4.87. MALDI TOF MS (DHB), m/z (%) 249 (M þ H , 63), 155(60),
137(100), 121(41).
Pure fractions containing compound
8 were collected and
0
2.4. Synthesis of 4 -ethynylflavanone 8
concentrated under vacuum, to yield 35.17 mg (94.5%) of com-
ꢁ
pound 8 as colorless crystals, mp. 132.8e134.0 C.
Potassium hydroxide (2.0 g, 35 mmol) dissolved in methanol
0
(
(
30 mL) was mixed, portion wise, with 2 -hydroxyacetophenone 4
2.7. X-ray data collection, structure determination, and refinement
0.18 mL; 1.54 mmol) and allowed to react for 20 min. Then, 4-
ethynylbenzaldehyde 3 (200 mg, 1.54 mmol) was added, and
allowed to react for 24 h at room temperature. Finally, the mixture
was neutralized (pH ¼ 7) with diluted hydrochloric acid, extracted
with ethyl acetate and dried with anhydrous magnesium sulfate,
filtered and concentrated under vacuum. The solid mixture formed,
containing a mixture of compounds 7 and 8, was submitted to
column chromatography (silica gel 60, ethyl acetate: hexane ¼ 1:10
v/v). Only pure fractions containing compound 8 were collected
and concentrated under vacuum, to yield 168 mg (44.2%) of com-
pound 8. the solid obtained was redissolved in Ethanol and allowed
X-ray quality crystals of compounds 5, 7 and 8 were obtained as
described below in this section. In each case, well-shaped crystals
were mounted with epoxy cement on the tip of a glass fiber in a
random orientation. A summary of the experimental and crystal-
lography data for each compound are given in Tables 1e3 for
compounds 5, 7 and 8, respectively. Crystallographic data were
collected at 296.15 K on a D8 Smart Apex II Bruker AXS diffrac-
tometer using a X-ray source Mo-K
a
radiation (
l
¼ 1.72 Å). The
structures were solved using OLEX2 [17] with the ShelXS structure
solution program using direct methods. Data were refined with
ShelXL refinement package using full-matrix least squares tech-
to crystallize by evaporation of the solvent, to yield colorless crys-
ꢁ
tals, mp. 132.8e134.0 C; IR (KBr):
n
¼ 3275 (H-C≡C), 2109 (C≡C),
2
niques based on F . All non-hydrogen atoms were refined with
1
1
688 (C]O), 1071 (-O-). H NMR (400 MHz, CDCl
3
):
d
¼ 2.90 (1H,
anisotropic displacement parameters.
included in their calculated positions. Crystallographic data
excluding structure factors) for the structures in this paper have
H atoms were finally
2
3
2
dd, H
c
,
J ¼ 16.8 Hz, J ¼ 3 Hz), 3.05 (1H, dd, H
b
,
,
J ¼ 16.8 Hz,
3
3
J ¼ 13.1 Hz), 3.11 (1H, s, ≡C-H), 5.50 (1H, dd, H
a
J ¼ 13.1 Hz;
(
3
3
3
J ¼ 3 Hz), 7.06 (2H, d, H
2
0
, J ¼ 7.8 Hz), 7.45 (2H, d, H
3
0
, J ¼ 8.2 Hz),
been deposited at the Cambridge Crystallographic Data Centre as
supplementary publications no. 1434464 (5), 1434460 (7) and
434458 (8). Copies of the data can be obtained, free of charge, on
3
0
7
.51 (1H, dd, H
5
,
J ¼ 8.34 Hz; J ¼ 1.26 Hz) 7.56 (2H, d, H
3
0
,
3
3
13
J ¼ 8.2 Hz), 7.94 (1H, dd, H7, J ¼ 8.2 Hz; J ¼ 1.53 Hz). C NMR
100.6 MHz, CDCl ):
3.5 (C2), 118.5 (C8), 121.3 (C6), 122.2 (C4) , 123.0(C4a), 126.4 (C2
1
(
8
3
d
¼ 45.0 (C3), 78.3 (H-C≡C-), 79.5 (H-C≡C-),
0
0
(
0
0
0
0
and C6 ), 127.5 (C5), 133.0 (C3 and C5 ), 136.7 (C7), 139.7 (C1 ), 161.8
C8a), 191.9 (-C]O). Analysis calculated for C17 : C, 82.24; H,
.87; O, 12.89. Found: C, 81.13; H, 4.87. MALDI TOF MS (Antracene)
m/z (%) 249 (M þ H , 100), 147 (4.4).
(
12 2
H O
3
. Results and discussion
4
þ
3
.1. Synthesis and characterization
0
2
.5. Synthesis of 4 -(trimethylsilylethynyl)-flavanone 9
Synthesis of 2 and 3 were performed following a previously
described methodology [18], reacting the 4-bromobenzaldehyde 1
0
4
3
-bromo-flavanone 6 (280 mg, 0.92 mmol), Pd(PPh) Cl (33 mg,
5
%, 0.047 mmol), CuI (18 mg, 10%, 0.09 mmol) and triethylamine
(
20 mL) were mixed in a Schlenk tube under Argon. Then, TMS-
Table 1
acetylene (0.13 mL, 0.92 mmol) was added and the mixture was
allowed to react at 65 C overnight. Then, the mixture was
Crystal data and structure refinement of compound 5.
ꢁ
Empirical formula
Formula weight
Temperature/K
Crystal system
Space group
a/Å
15 2
C H11BrO
303.15
296.15
concentrated under vacuum, redissolved in methylene chloride and
filtered through Celite. The filtrate was concentrated under vacuum
and submitted to column chromatography. (Silica gel 60, ethyl ac-
etate: hexane ¼ 1:20 v/v) the pure fractions containing the com-
pound 9 were concentrated in vacuo to yield a pale yellow solid
monoclinic
P2 /c
1
8.6993(16)
6.8733(13)
20.778(4)
90
89.861(9)
90
1242.4(4)
4
1.621
b/Å
(
0.43 mmol; 137.6 mg, 50%) the obtained solid was redissolved in
c/Å
ꢁ
ꢁ
ꢁ
/
a
b
g
/
/
ethanol and allowed to crystallize by evaporation of the solvent, to
yield a pale yellow crystals, mp. 93.9e96.1 C; IR (KBr):
ꢁ
n
¼ 2160
1
(
(
(
TMS), 1694 (C]O), 1068 (-o-); H NMR (400 MHz, CDCl
3
):
d
: 7.86
3
Volume/Å
Z
0
0
1H, d, J ¼ 7.8 Hz, H7), 7.45 (3H, m, J ¼ 8.0 Hz, H5, H3 and H5 ), 7.35
0
0
3
2H, d, J ¼ 8.1 Hz, H2 and H4 ), 6.99 (2H, dd, J ¼ 8.0 Hz, J ¼ 5.3 Hz,
r
calcg/cm
ꢀ
1
m
/mm
3.298
608.0
H6 and H8), 5.40 (1H, dd, J ¼ 13.1 Hz, J ¼ 2.9 Hz, H2), 2.96 (1H, dd,
F(000)
J ¼ 16.8 Hz, J ¼ 13.1 Hz, H3), 2.81 (1H, dd, J ¼ 16.9, 3.0 Hz, H3), 0.19
Crystalsize/mm3
0.5 ꢂ 0.34 ꢂ 0.19
(
3 3
s, 9H, (CH ) -Si-).
Radiation
MoK
3.92 to 60.506
a
(
l
¼ 0.71073)
1
3
ꢁ
C NMR (100.6 MHz, CDCl
3
):
d
¼ 1.1 ((CH
3
)
3
-Si-), 44.6 (C3),
2
Q
range for data collection/
Index ranges
ꢀ12 ꢃ h ꢃ 10, ꢀ9 ꢃ k ꢃ 9, ꢀ28 ꢃ l ꢃ 28
7
(
9.2(TMS-C≡C-Ar), 95.2(C2), 104.5 (TMS-C≡C-Ar), 118.2(C8), 121.0
C6), 121.8 (C4 ), 123.7 (4a), 126.0 (C2 and C6 ), 127.1 (C5), 132.5 (C3
0
0
0
0
Reflections collected
Independent reflections
Data/restraints/parameters
Goodness-of-fiton F2
14897
3382 [Rint ¼ 0.0815, Rsigma ¼ 0.0947]
0
0
and C5 ), 136.3 (C7), 139.0 (C1 ), 161.4 (8a), 191.7 (C4).
3382/0/164
0.890
0
2
.6. Alternative synthesis of 4 -ethynylflavanone 8
Final R indexes [I ꢄ 2
s
(I)]
R
R
1
1
¼ 0.0516, wR
2
2
¼ 0.1278
¼ 0.1671
Final R indexes [all data]
Largest diff. peak/hole/e Å
¼ 0.1369, wR
ꢀ
3
0.57/-0.78
0
4
-(trimethylsilylethynyl)-flavanone 9 (48.37 mg, 0.14 mmol)